Crystal structure of the Entamoeba histolytica RNA lariat debranching enzyme EhDbr1 reveals a catalytic Zn2+/Mn2+ heterobinucleation.

Autor:	Ransey, Elizabeth, Paredes, Eduardo, Dey, Sourav K., Das, Subha R., Heroux, Annie, Macbeth, Mark R.
Předmět:	ENTAMOEBA histolytica CRYSTAL structure PHOSPHATASES PHOSPHODIESTERS RNA
Zdroj:	FEBS Letters; Jul2017, Vol. 591 Issue 13, p2003-2010, 8p
Abstrakt:	The RNA lariat debranching enzyme, Dbr1, is a metallophosphoesterase that cleaves 2′-5′ phosphodiester bonds within intronic lariats. Previous reports have indicated that Dbr1 enzymatic activity is supported by diverse metal ions including Ni2+, Mn2+, Mg2+, Fe2+, and Zn2+. While in initial structures of the Entamoeba histolytica Dbr1 only one of the two catalytic metal-binding sites were observed to be occupied (with a Mn2+ ion), recent structures determined a Zn2+/Fe2+ heterobinucleation. We solved a high-resolution X-ray crystal structure (1.8 Å) of the E. histolytica Dbr1 and determined a Zn2+/Mn2+ occupancy. ICP- AES corroborate this finding, and in vitro debranching assays with fluorescently labeled branched substrates confirm activity. [ABSTRACT FROM AUTHOR]
Databáze:	Complementary Index
Externí odkaz:	Zobrazit plný text záznamu Plný text